Apparatus and method for supplying powder quantitatively and material supplying apparatus including the apparatus for supplying powder

ABSTRACT

Provided are an apparatus and method for supplying powder quantitatively and a material supply apparatus including the apparatus for supplying powder quantitatively. The apparatus for supplying powder quantitatively to a place where required includes: a driving part generating a driving force using an external power; a powder supply part connected to the driving part, following the operation of the driving part, and transferring the powder according to a predetermined path; a chamber placed on the sides of the powder supply part and receiving the powder transferred by the powder supply part; a compression part compressing the transferred powder in the chamber; and a quantitative supply part separating a desired amount of powder from the compressed powder and discharging the separated powder from the chamber. The method of supplying powder quantitatively to a place where required includes: a preparation operation of receiving powder and preparing for the transfer of the powder; a powder transfer operation of transferring the powder to a chamber having a predetermined volume according to a predetermined path using a powder supply part that is driven by an external power and transfers the powder; a compressing operation of making the compressed bulk of powder by compressing the transferred powder in a compression part of the chamber; a separating operation of separating a desired amount of powder from the powder that is compressed and bridged in the chamber using a separating means; and a discharge operation of discharging the separated powder to the outside.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application claims the benefit of Korean Patent Application Nos.10-2005-0043208 and 10-2006-0042832, filed on May 23, 2005 and May 12,2006, in the Korean Intellectual Property Office, the disclosure ofwhich are incorporated herein in their entirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus and method for supplyingpowder quantitatively and a material supplying apparatus including theapparatus for supplying powder quantitatively.

2. Description of the Related Art

Plastic goods having a desired color or special function can be producedby using additives having the desired color or special function inplastic materials (e.g., LDPE, EVA, PP, PET, PC, PVC, etc.) whilemolding the plastic materials using a process of extrusion or injection.

However, since additives are mostly powder or liquid, it is technicallydifficult to uniformly mix them with the plastic materials and thus theplastic materials have a different distribution density, making thecolor of the plastic goods bridged or spotted. Therefore, it is verydifficult to produce plastic goods having the desired color or specialfunction.

To uniformly mix powder with the plastic materials, the plasticmaterials are previously coated with a required amount of powder, thepowder and the plastic materials are fused by melting them together, orconcentrated powder is provided to the plastic materials using acarrier, etc. However, since it is necessary to separately measure ortransfer the powder, the plastic goods have a very low productivity, andthe measured amount of powder is different from the used amount ofpowder, causing the plastic goods to be of low quality.

To solve the problem of the conventional methods, a gravimetricquantitative feeding method using a microbalance or a volumetricquantitative feeding method using a micro-screw have been suggested.However, since these two methods cannot prevent the powder frombridging, generating static electricity, and flying into air due to themeasurement or transfer of the powder, it is difficult to supply powderquantitatively.

SUMMARY OF THE INVENTION

The present invention provides an apparatus and method for supplyingpowder quantitatively that does not prevent powder from being bridgedbut derives bridging property in order to avoid an ununiform supply ofquantitative powder due to a partial change in the bulk density of thepowder caused by an external factor such as pressure, moisture, staticelectricity or the like which is applied to the powder being held ortransferred, compresses the powder completely thereby uniforming bulkdensity of the transferred powder, and measures a predetermined volumeof the powder by precisely separating a necessary amount of the powderfrom the compressed powder, thereby precisely controlling the amount ofsupplied powder, and a material supply apparatus that mixes the powderprovided by the apparatus for supplying powder quantitatively and aplastic material effectively.

According to an aspect of the present invention, there is provided anapparatus for supplying powder quantitatively to a place where required,the apparatus comprising: a driving part generating a driving forceusing an external power; a powder supply part connected to the drivingpart, following the operation of the driving part, and transferring thepowder according to a predetermined path; a chamber placed on the sidesof the powder supply part and receiving the powder transferred by thepowder supply part; a compression part compressing the transferredpowder in the chamber; and a quantitative supply part separating adesired amount of powder from the compressed powder and discharging theseparated powder from the chamber.

The driving part may comprise a gear box comprising: a plurality ofgears receiving a rotational torque from outside and rotating at apredetermined speed ratio; and a plurality of rotation shafts fixed tothe gears and rotating about their axes by the rotation of the gears,and extending in a longitudinal direction.

The powder supply part may comprise: an upper plate fixed outside of thegear box and through which one or more than one rotation shafts of theplurality of rotation shafts passes; and a powder pushing unit equippedon the upper plate, rotating clockwise or counterclockwise in contactwith the upper surface of the upper plate by the rotation shafts, andtransferring the powder to the chamber.

The chamber may comprise a sub-supply block comprising: a first spacepart with a predetermined diameter and depth opened toward the powdersupply part to receive the powder provided by the powder supply part,and through which one of the rotation shafts of the gear box passesupward and is disposed in the center thereof; and a second space partwith a predetermined diameter and depth formed at the sides of the firstspace part, opened to the first space part to receive the powder fromthe first space part, and through which another rotation shaft of thegear box passes upward and is disposed in the center thereof.

The compression part may comprise: at least one feeding gear placedinside the first space part and rotating by the rotation shafts andhaving a plurality of gear teeth transferring the powder provided by thepowder supply part to the second space part; a transfer disk placedinside the second space part and rotating by the rotation shafts, andhaving a circular arc powder pressing groove, and receiving thecompressed powder transferred through the feeding gear; and a cover mainbody placed on the transfer disk, partly covering the powder pressinggroove, and supporting the powder to the powder pressing groove.

The quantitative supply part may comprise a blade having a leading endpart entering into the powder pressing groove, partly cutting thecompressed powder in the powder pressing groove during the rotation ofthe transfer disk, and discharging the cut powder from the second spacepart.

The apparatus may further comprise; a crushing pin fixed in the covermain body and crushing the compressed bulk of powder while the bridgedpowder is being transferred and compressed by the feeding gear, andtransferring the crushed powder to the powder pressing groove.

The transfer disk may comprise: an inner disk having a predetermineddiameter and rotating by the rotation shaft; an outside ring having thesame axis as the inner disk, and the inner circumference spaced apartfrom the exterior circumference of the inner disk forming the powderpressing groove; and a packing member inserted into the lower part ofthe powder pressing groove and upwardly supporting the powder stored inthe powder pressing groove.

A projection is formed at the bottom part of the second space part topress the powder approaching the blade to the cover main body by movingthe packing member of the transfer disk upward.

The apparatus may further comprise: a powder storing case attached tothe upper part of the upper plate and storing powder to be provided fromoutside in which the upper part acts as a bottom surface, wherein thepowder pushing unit comprises; a fixing unit fixed to the rotation shaftand being symmetrical around the rotation shaft; a tip unit placed inboth ends of the fixing unit and moving in a length direction of thefixing unit; and a spring disposed between the fixing unit and the tipunit and elastically supporting the tip from the fixing unit toexternally, wherein two or more projections temporally compressing thetip unit of the pushing unit to the fixing unit during the rotation ofthe pushing unit are formed in the inner circumference of the powderstoring case.

The apparatus may further comprise: a porous plate spaced parallel apartfrom the upper plate in the inner surface of the powder storing case andhaving a plurality of through holes passing downward the powder providedfrom outside; and an auxiliary rotor placed on the upper surface of theporous plate, rotating by the rotation shaft, and inducing the powder tothe through holes.

According to another aspect of the present invention, there is provideda material supply apparatus comprising: an upper duct passing anexternally provided plastic raw material having a quantitative powdersupply device that discharges powder to be mixed with the plastic rawmaterial; a rotation duct rotatably equipped at the lower part of theupper duct and including a stirring unit mixing the plastic raw materialwith the powder; a lower duct placed below the lower part of therotation duct, rotatably supporting the rotation duct, and discharging amixture of the plastic raw material and powder downwardly that passesthrough the rotation duct to the outside; bearings disposed between theupper duct and the rotation duct and between the lower duct and therotation duct, rotatably supporting the rotation duct, and forming aseal between the rotation duct and the upper and lower ducts; and adriving unit axis-rotating the rotation duct and operating the stirringunit.

The stirring unit may be at least one steel wire fixed in the innercircumference of the rotation duct.

According to another aspect of the present invention, there is provideda method of supplying powder quantitatively to a place where required,the method comprising: a preparation operation of receiving powder andpreparing for the transfer of the powder; a powder transfer operation oftransferring the powder to a chamber having a predetermined volumeaccording to a predetermined path using a powder supply part that isdriven by an external power and transfers the powder; a compressingoperation of compressing the transferred powder in a compression part ofthe chamber; a separating operation of separating a desired amount ofpowder from the powder that is compressed and bridged in the chamberusing a separating means; and a discharge operation of discharging theseparated powder to the outside.

The power supply part may comprise: a plurality of gears receiving arotational torque from outside and rotating at a predetermined speedratio; and a rotor rotating by the rotational power of the gears andtransferring the powder, wherein, in the powder transfer operation, thepowder is transferred to the chamber using the rotor.

The compression part performing the compressing operation may comprise apressing tool pressing the powder, and a compression frame storing thepowder and transferring pressure to the powder, wherein, in thecompressing operation, the powder transferred through the powdertransfer operation is compressed by the operation of the compressionpart.

In the separating operation, the separating means may be used tovolume-separate the powder from the compressed powder by entering ablade in a relative motion with regard to the powder into the compressedpowder in chamber to a predetermined depth.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features and advantages of the present inventionwill become more apparent by describing in detail exemplary embodimentsthereof with reference to the attached drawings in which:

FIG. 1 is a perspective view of an apparatus for supplying powderquantitatively according to an embodiment of the present invention;

FIG. 2 is an exploded perspective view of the apparatus for supplyingpowder quantitatively illustrated in FIG. 1;

FIG. 3 is a side cross-sectional view of a gearbox included in theapparatus for supplying powder quantitatively illustrated in FIG. 1;

FIG. 4 is a cross-sectional perspective view of a powder storing caseillustrated in FIG. 1;

FIG. 5 is a partial cross-sectional view of a rotor illustrated in FIG.2;

FIG. 6 is a cross-sectional view of a powder storing case applied to theapparatus for supplying powder quantitatively according to anotherembodiment of the present invention;

FIG. 7 is a cross-sectional view of a transfer disk taken along a lineVII-VII illustrated in FIG. 2;

FIGS. 8 and 9 are plan views for illustrating an operating mechanism ofthe apparatus for supplying powder quantitatively according to anembodiment of the present invention;

FIG. 10 is a cross-sectional view of a material supply apparatusaccording to an embodiment of the present invention; and

FIG. 11 is a flowchart illustrating a method of supplying powderquantitatively according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will now be described more fully with reference tothe accompanying drawings.

FIG. 1 is a perspective view of an apparatus 10 for supplying powderquantitatively according to an embodiment of the present invention.Referring to FIG. 1, the apparatus 10 for supplying powderquantitatively comprises a gear box 12 receiving a rotating torque fromoutside and including three shafts (30, 34, and 36 illustrated in FIG.2) on the upper portion thereof, an upper plate 38 and a quantitativesupply part 48 placed on the upper part of the gear box 12, a powderstoring case 40 attached to the upper part of the upper plate 38 andstoring powder to be provided, a rotor 60 rotating inside the powderstoring case 40 and supplying the powder to the quantitative supply part48, and a compression plate 50 sealing the upper part of thequantitative supply part 48.

The gear box 12 rotates the three shafts 30, 34, and 36 in the samedirection and at a predetermined speed ratio. The gear box 12 will nowbe described with reference to FIG. 3. FIG. 3 is a side cross-sectionalview of the gearbox 12 included in the apparatus for supplying thequantitative powder illustrated in FIG. 1. Referring to FIG. 3, the gearbox 12 comprises a casing 32 enclosing an inner space of the gear box12, a worm 16 horizontally installed inside the casing 32 and rotates bythe torque received from a motor (not shown) outside through a drivingshaft 14, a worm gear 18 engaged with the worm 16, a first gear 20 fixedinto the upper part of the worm gear 18, and the first shaft 30receiving the rotating torque from the first gear 20, extending upwardto the upper part of the casing 32, and passing through the upper plate38.

The gear box 12 further comprises a first middle gear 26, a second gear22, a second middle gear 28, and a third gear 24 next to the first gear20. The second gear 22 and the third gear 24 have the same size and thusare identical to each other in terms of rotating speed and direction.The first gear 20 and the second gear 22 can have a gear ratio between3:1 and 4:1.

The second shaft 34 is fixed in the rotation center of the second gear22, and the third shaft 36 is fixed in the rotation center of the thirdgear 24. The second shaft 34 and the third shaft 36 extend to the upperpart of the casing 32 and are parallel to each other.

The first shaft 30 rotates a rotor 60, and the second shaft 34 rotates afeeding gear (48 m illustrated in FIG. 2.), and the third shaft 36rotates a transfer disk (52 illustrated in FIG. 2).

Referring to FIG. 1, the upper plate 38 placed on the upper part of thegear box 12 is a metal block providing a flat surface on which thepowder storing case 40 is attached. The upper surface of the upper plate38 and the lower part of the powder storing case 40 are connected toeach other so that powder does not leak out.

A support plane (38 a illustrated in FIG. 2) with a predetermineddiameter is projected from the upper center of the upper plate 38. Thesupport plane 38 a acts as a bottom surface of the powder storing case40. The rotor 44 goes over the support plane 38 a.

The powder storing case 40 comprises a sealing ring 40 a tightlyattached to the upper plate 38 and including the support plane 38 a, acylindrical case body 40 b fixed to the sealing ring 40 a and extendingto the upper part thereof, and a cap 42 covering the case body 40 b andsealing the case 40. The case body 40 b and the cap 42 can be formed ofa transparent acryl.

The sealing ring 40 a includes a projection 40 c in its innercircumference. The end parts of the rotor 60 that rotates in a directionp cross over the projection 40 c having an incline surface (40 eillustrated in FIG. 4). The incline surface 40 e moves elastic tips 60 bthat are end parts of the rotor 60 in a direction t. If the elastic tips60 b move in the direction t, a spring (60 h illustrated in FIG. 5)disposed between the elastic tips 60 b and a fixing rod 60 a iscompressed.

Therefore, when the end parts of the rotor 60 cross over the projection40 c, the elastic tips 60 b instantly moves in an opposite direction ofthe direction t from the fixing rod 60 a via an elastic restorationforce, causing a shock. This will be in detail described with referenceto FIG. 5. Powder on the rotor 60 is separated from the rotor 60 due tothe shock generated when the rotor 60 crosses over the projection 40 c.

The quantitative supply part 48 receives powder through a first space 48b which is partially included in the inner space of the powder storingcase 40, compresses the powder, separates a desired amount of the powderfrom the compressed powder using a blade (56 b illustrated in FIG. 2),and discharges the desired amount of the power to an outlet 48 c.

The compression plate 50 covers the quantitative supply part 48, pressesa disk cover (56 illustrated in FIG. 2), and simultaneously seals theinner space of the quantitative supply part 48 to prevent externalimpurities from entering into the quantitative supply part 48.

FIG. 2 is an exploded perspective view of the apparatus for supplyingthe quantitative powder illustrated in FIG. 1. Referring to FIG. 2, thefirst, second, and third shafts 30, 34, and 36 extend upward from thegear box 12. The first shaft 30 passes through the upper part of theupper plate 38 and is located at the center of the support plane 38 a.

A storing groove 38 b that stores a part of the quantitative supply part48 is formed in a portion of the support plane 38 a. The storing groove38 b is a stepped groove and enters into the support plane 38 a.

The maximum length of the rotor 60 is the same as the diameter of thesupport plane 38 a. This means that the storing groove 38 b is partlyincluded in a rotation radius of the rotor 60 so that the powdertransferred by the rotor 60 can be supplied to the quantitative supplypart 48 under the powder storing case 40.

The rotor 60 is coupled to the first shaft 30 via a bolt 46 and rotateson the support plane 38 a. The bottom surface of the rotor 60 faces theupper surface of the support plane 38 a. At this time, the powderbetween the rotor 60 and the support plane 38 a acts as a lubricant. Afemale screw hole 30 a coupled with the bolt 46 is formed on the upperend part of the first shaft 30. Therefore, if necessary, the rotor 60can be easily separated from the first shaft 30. A leading end part ofthe compression plate 50 is inserted into a compressed plate insertinggroove 40 d.

The quantitative supply part 48 comprises a sub-supply block 48 a partlyinserted into the storing groove 38 b, formed on the upper part of thegear box 12, and includes first and second space parts 48 b and 48 g onthe upper part thereof, the feeding gear 48 m screwed into the firstspace part 48 b, the transfer disk 52 rotatably placed in the secondspace part 48 g, and the disk cover 56 fixed to the upper part of thetransfer disk 52 and downwardly supporting the transfer disk 52.

The upper surface of the sub-supply block 48 a is flat and tightly facesthe bottom surface of the compression plate 50.

The first space part 48 b is a circular groove with a predetermineddiameter and depth and has a through hole 48 d in the center of thebottom surface 48 f. The through hole 48 d vertically perforates thesub-supply block 48 a and passes through the upper part of the secondshaft 34. The second shaft 34 is coupled to the feeding gear 48 m insidethe first space part 48 b and rotates the feeding gear 48 m in adirection.

The feeding gear 48 m has a plurality of gear teeth 48 n at a regularinterval in its outer circumference. In particular, the gear teeth 48 nare divided into up and down in order to rotate the feeding gear 48 m byentering a crushing pin 56 c into the gear teeth 48 n as described inFIG. 9.

The feeding gear 48 m operates like a gear pump, receives the powderprovided by the rotor 60 to the first space part 48 b, and moves thepowder to the second space part 48 g, which will be described in detailwith reference to FIG. 8. The powder is compressed and bridged whilebeing transferred by the feeding gear 48 m.

The second space part 48 g is a circular groove having a predetermineddiameter and is deeper than that of the first space part 48 b. In thecurrent embodiment, the inner diameter of the second space part 48 g isidentical to that of the first space part 48 b, but the presentinvention is not necessarily restricted thereto.

The second space part 48 g is simultaneously opened upwardly toward thefirst space part 48 b in order to receive the powder through the firstspace part 48 b.

A through hole 48 e is formed in the center of the bottom surface 48 hof the second space part 48 g. The through hole 48 e is verticallyformed in the sub-supply bock 48 a and is passed through by the upperpart of the third shaft 36. The third shaft 36 is inserted into thetransfer disk 52 to rotate the transfer disk 52. The transfer disk 52and the feeding gear 48 m are identical to each other in terms ofrotational speed and direction.

A projection 48 k is formed in the sides of the through hole 48 e. Theprojection 48 k is formed on the bottom surface of the second space part48 g closer to a wall, and pushes a packing ring 54, which rotates in adirection m, of the lower part of the transfer disk 52 in a direction f(illustrated in FIG. 9).

The transfer disk 52 comprises an inner disk 52 d having a predetermineddiameter and including a shaft insertion hole 52 a into which the thirdshaft 36 is inserted, an outside ring 52 e surrounding an inner disk andforming a powder pressing groove 52 b having a predetermined width withthe inner disk 52 d, and the packing ring 54 inserted into the powderpressing groove 52 b at the lower part of the transfer disk 52.

The packing ring 54 packs the lower part of the powder pressing groove52 b to prevent powder pressed in the powder pressing groove 52 b fromleaking and upwardly press the powder against the disk cover 56 afterbeing pushed upwardly by the projection 48 k. The powder pressing groove52 b stores the powder supplied by the feeding gear 48 m and forms acircular arc having a predetermined width.

The disk cover 56 is formed of a Teflon resin having a predeterminedthickness and covers a part of the powder pressing groove 52 b using thebottom surface thereof. The disk cover 56 comprises a cover body 56 ainserted into the second space part 48 g and downwardly supporting thetransfer disk 52, the crushing pin 56 c fixed on a portion of the coverbody 56 a, and the blade 56 b fixed at the opposite side of the coverbody 56 a to the crushing pin 56 c.

A circular arc-shaped groove 56 e is formed at the outer circumferenceof the cover body 56 a toward the feeding gear 48 m. The circulararc-shaped groove 56 e has the same curvature as the outer circumferenceof the feeding gear 48 m and opens the powder pressing groove 52 bupwardly as illustrated in FIG. 8.

The crushing pin 56 c is fixed into the circular arc-shaped groove 56 e.The crushing pin 56 c, which is an iron core extending toward betweenthe gear teeth 48 n, crushes (bridged) compressed powder between thegear teeth 48 n so that the powder pressing groove 52 b can easilyaccommodate the crushed powder.

The blade 56 b is fixed in the opposite side of the cover body 56 a tothe crushing pin 56 c. The leading end portion of the blade 56 b fixedinto the cover main body 56 a extends inside the powder pressing groove52 b. The maximum length of the blade 56 b that enters into the powderpressing groove 52 b can be controlled according to circumstances and isin a range of about 1 mm to 3 mm.

The compression plate 50 is put on the upper part of the sub-supplyblock 48 a after the feeding gear 48 m, the transfer disk 52, and thedisk cover 56 are installed in the first and second space parts 48 b and48 g. The compression plate 50 supports the disk cover 56 and thefeeding gear 48 m and simultaneously seals a part of the first spacepart 48 b and the second space part 48 g. The compression plate 50 canbe coupled to the sub-supply block 48 a using any coupling methods.

FIG. 3 is a side cross-sectional view of the gearbox 12 included in theapparatus for supplying the quantitative powder 10 illustrated in FIG.1.

FIG. 4 is a cross-sectional perspective view of the powder storing case40 illustrated in FIG. 1. Referring to FIG. 4, the powder storing case40 comprises the sealing ring 40 a that is tightly attached to the upperplate 38, and the case body 40 b of which a lower part is connected tothe sealing ring 40 a and extends upwardly. The projection 40 c isformed in the inner circumference of the sealing ring 40 a. The numberof the projection 40 c can be changed according to circumstances.

FIG. 5 is a partial cross-sectional view of the rotor 60 illustrated inFIG. 2. Referring to FIG. 5, the rotor 60 comprises the fixing rod 60 aincluding the through hole 60 d through which the bolt 46 passesdownward in the center thereof and fixed to the first shaft 30, theelastic tips 60 b place in both ends of the fixing rod 60 a, and thespring 60 h disposed between the fixing rod 60 a and the elastic tips 60b and supporting the elastic tips 60 b in the direction p.

An insertion end part 60 e that is thin and integrally formed with aguide pin 60 f in the upper surface thereof is disposed at both ends ofthe fixing rod 60 a. The insertion end part 60 e has a predeterminedthickness and is inserted into a storing part 60 k of the elastic tips60 b. The guide pin 60 f is a projection having a long ovalcross-section in the length direction of the rotor 60.

The elastic tips 60 b stores the insertion end part 60 e and issupported by the spring 60 h in the direction p. A long hole 60 gthrough which the guide pin 60 f is inserted is formed in the elastictips 60 b. The long hole 60 g stores the guide pin 60 f and guides theelastic tips 60 b to move in the length direction.

When the rotor 60 having the above structure rotates, the elastic tips60 b cross over the incline surface 40 e of the projection 40 c and iscompressed in the opposite direction of p. When the elastic tips 60 bpass through the projection 40 c, the elastic tips 60 b springs out inthe direction p by the operation of the spring 60 h so that the guidepin 60 f collides with the inner circumference of the long hole 60 g,generating a shock. The shock detaches the powder from the rotor 60.

FIG. 6 is a cross-sectional view of a powder storing case applied to theapparatus for supplying quantitative powder according to anotherembodiment of the present invention. Referring to FIG. 6, the case body40 b comprises a porous plate 62 and an auxiliary rotor 64. The porousplate 62 is a disk type constituent having a plurality of through holes62 a and is horizontally fixed to the upper part of the rotor 60.

The auxiliary rotor 64 is placed on the upper surface of the porousplate 62, is fixed via the bolt 46, and rotates with the rotor 60. Theporous plate 62 bears the weight of powder provided from outside toprevent the rotor 60 from being pressed by the weight of the powder. Theauxiliary rotor 64 is used to drop the powder at a uniform distributionthrough the through holes 62 a of the porous plate 62.

A nut 91 fixes the rotor 60 into the first shaft 30.

FIG. 7 is a cross-sectional view of the transfer disk 52 taken along aline VII-VII illustrated in FIG. 2. Referring to FIG. 7, the powderpressing groove 52 b having a predetermined width is disposed betweenthe inner disk 52 d and the outside ring 52 e. The packing ring 54 isinserted into the lower part of the powder pressing groove 52 b to sealthe lower part of the powder pressing groove 52 b.

FIGS. 8 and 9 are plan views for illustrating an operating mechanism ofthe apparatus 10 for supplying powder quantitatively according to anembodiment of the present invention. Referring to FIGS. 8 and 9, thefeeding gear 48 m is mounted in the first space part 48 b of thesub-supply block 48 a, and the transfer disk 52 and the disk cover 56are mounted above and below in the second space part 48 g. The feedinggear 48 m and the transfer disk 52 rotate in the direction s.

As indicated by a dotted line, a part of the first space part 48 b isincluded in the powder storing case 40. Therefore, powder is pushed intothe first space part 48 b in the direction z1 by the rotor 60 rotatingin the direction s.

The powder pushed into the first space part 48 b is stored between thegear teeth 48 n of the feeding gear 48 m, moves in the direction Y bythe continuous rotation of the feeding gear 48 m, and is compressedbetween the inner circumference of the first space part 48 b. The powdermoved in the direction Y enters into the lower part of the compressionplate 50 so that the powder is separated from outside and is not blownaway.

The powder that is transferred in the direction Y by the feeding gear 48m and is compressed by the compression plate 50 is crushed by thecrushing pin 56 c. Since the powder transferred by the feeding gear 48 mis compressed and bridged between the gear teeth 48 n, the powder canmove inside the powder pressing groove 52 b (in the direction z2) afterbeing crushed by the crushing pin 56 c.

The powder crushed by the crushing pin 56 c moves inside the powderpressing groove 52 b of the transfer disk 52 that rotates, and fills upthe powder pressing groove 52 b. Since the powder pressing groove 52 band the gear teeth 48 n of the upper part of the powder pressing groove52 b cross each other, the powder is pressed by the gear teeth 48 n andpressed in the powder pressing groove 52 b.

The powder that filled up the powder pressing groove 52 b is compressedagain the bottom surface of the cover main body 56 a, and moves to theblade 56 b in the direction Y2. The powder of the powder pressing groove52 b is pressed by the bottom surface of the cover body 56 a to flattenthe upper surface thereof.

In particular, the projection 48 k formed on the bottom surface of thesecond space part 48 g pushes up the packing ring 54 in the direction fso that the powder is strongly pressed upwardly and is relativelycompressed by the bottom surface of the cover body 56 a.

The blade 56 b cuts off the upper part of the powder that has arrived atthe leading end part of the blade 56 b so that the cut powder isdischarged through the outlet 48 c in the direction z3. The amount ofdischarged powder can be changed by the length of the leading end partof the blade 56 b that enters into the powder pressing groove 52 b orthe rotational speed of the transfer disk 52.

The powder passing below the blade 56 b moves to the feeding gear 48 magain and is mixed with newly provided powder.

FIG. 10 is a cross-sectional view of a material supply apparatus 70according to an embodiment of the present invention. The material is amixture of plastic raw materials and powder.

Referring to FIG. 10, the material supply apparatus 70 comprises a pipetype upper duct 72 fixing the apparatus 10 for supplying quantitativepowder in an inclined condition, a rotation duct 74 placed at the lowerpart of the upper duct 72, a lower duct 76 placed at the lower part ofthe rotation duct 74, rotatably supporting the rotation duct 74 anddownwardly transferring the material, a motor 84 rotating the rotationduct 74. The upper duct 72 is a pipe having a predetermined diameter anddownwardly transfers plastic raw material through a separately attachedhopper (not shown). The plastic raw material falls down with thequantitative powder discharged by the apparatus 10 for supplying thequantitative powder while being transferred downward.

The rotation duct 74 is a pipe having the same size as the upper duct 72and includes a stirring steel wire 90. The stirring steel wire 90 is alinear constituent that mixes the plastic raw material with the powder.The stirring steel wire 90 is fixed to the rotation duct 74 by insertingboth ends of the stirring steel wire 90 into a groove 74 a formed in theinner circumference of the rotation duct 74 and welded with the rotationduct 74. The formation or number of the stirring steel wheel 90 can bechanged according to circumstances. Another stirring constituent canreplace the stirring steel wire 90.

The material supply apparatus 70 further comprises a sprocket 88, amotor 84, and a chain 86 to axis-rotate the rotation duct 74. Thesprocket 88 surrounds the outer circumference of the rotation duct 74and is coupled to a driving axis of the motor 84 using the chain 86.Therefore, if the motor 84 is operated, a driving force of the motor 84is transmitted to the sprocket 88 using the chain 86 and the rotationduct 74 axis-rotates so that the material is stirred.

Teflon bearings 82 are placed between the upper duct 72 and the rotationduct 74 and between the rotation duct 74 and the lower duct 76. TheTeflon bearings 82 are formed of conventional Teflon and are used torotate the rotation duct 74 between the upper duct 72 and the lower duct76. The Teflon bearings 82 block the inner space of the ducts 72, 74,and 76 from outside.

Supporting rods 78 and brackets 80 are used to maintain an intervalbetween the upper duct 72 and the lower duct 76. The brackets 80 areiron pieces fixed to the outer circumference of the upper duct 72 andthe lower duct 76.

The supporting rods 78 interconnect the brackets 80 of the upper duct 72and the lower duct 76. The upper and lower end parts of the supportingrods 78 are coupled to the brackets 80 of the upper duct 72 and thelower duct 76, respectively, to firmly maintain the interval between theupper duct 72 and the lower duct 76, which are spaced a predetermineddistance from rotation duct 74.

FIG. 11 is a flowchart illustrating a method of supplying powderquantitatively according to an embodiment of the present invention.Referring to FIG. 11, the method of supplying powder quantitativelycomprises a preparation operation 100 of receiving quantitative suppliedpowder from outside and preparing transfer of the powder, a powdertransfer operation 102 of transferring the powder to a chamber includingthe first and second space parts 48 b and 48 g according to apredetermined path, a compressing operation 104 of compressing thetransferred powder inside the first and second space parts 48 b and 48g, a separating operation 106 of separating a desired amount of thepowder from the powder pressed in the second space part 48 g using aseparating means, and a discharge operation 108 of discharging theseparated powder from the second space part 48 g.

In the preparation operation 100, the powder storing case 40 receivesthe powder. The powder storing case 40 is disposed on the upper plate 38and the inner circumference of the sealing ring 40 a is tightly attachedto the outer circumference of the support plane 38 a.

In the powder transfer operation 102, the powder stored in the powderstoring case 40 is transferred to the first space part 48 b of thequantitative supply part 48 by rotating the rotor 60.

In the compressing operation 104, the powder transferred to thequantitative supply part 48 is compressed through the first and secondspace parts 48 b and 48 g. Since the main gist of the present inventiontransfers completely compressed powder in order to avoid an ununiformsupply of quantitative powder due to a partial change in the bulkdensity caused by an external factor such as pressure, moisture, staticelectricity or the like which is applied to the power being held ortransferred, using of the bridging property, the supplied quantitativepowder is compressed and bridged (in the first and second space parts 48b and 48 g).

The powder is compressed by the rotation of the feeding gear 48 m andthe transfer disk 52. As described with reference to FIG. 8, while thefeeding gear 48 m and the transfer disk 52 rotate using the rotationalpower of the second and third shafts 34 and 36, the powder is pressedinto the powder pressing groove 52 e by the gear teeth 48 n of thefeeding gear 48 m.

In the separating operation 106, the desired amount of powder isseparated from the compressed (lump of) powder in the second space part48 g using the blade 56 b. Since the leading end part of the blade 56 benters into the powder pressing groove 52 b, the blade 52 b can separatethe powder while the transfer disk 52 moves in the direction Y2illustrated in FIG. 8.

In the discharge operation 108, the separated powder is discharged fromthe second space part 48 g in the direction z3 illustrated in FIG. 9.The powder discharged from the quantitative supply part 48 istransferred to a place where it is required.

The present invention does not prevent powder from being bridged butderives bridging property in order to avoid an ununiform supply ofquantitative powder due to a partial change in the bulk density of thepowder caused by an external factor such as pressure, moisture, staticelectricity or the like which is applied to the powder being held ortransferred, compresses the powder completely thereby uniforming bulkdensity of the transferred powder, and measures a predetermined volumeof the powder by precisely separating a necessary amount of the powderfrom the compressed powder, thereby precisely controlling the amount ofsupplied powder.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be understoodby those of ordinary skill in the art that various changes in form anddetail may be made therein without departing from the spirit and scopeof the present invention as defined by the following claims. Thepreferred embodiments should be considered in a descriptive sense onlyand not for purposes of limitation. Therefore, the scope of theinvention is defined not by the detailed description of the inventionbut by the appended claims, and all differences within the scope will beconstrued as being included in the present invention.

The invention claimed is:
 1. An apparatus for supplying powderquantitatively to a place where required, the apparatus comprising: adriving part generating a driving force using an external power; apowder supply part connected to the driving part, following theoperation of the driving part, and transferring the powder according toa predetermined path; a chamber placed on the sides of the powder supplypart and receiving the powder transferred by the powder supply part; acompression part compressing the transferred powder in the chamber; anda quantitative supply part separating a desired amount of powder fromthe compressed powder and discharging the separated powder from thechamber, wherein the compression part comprises at least one feedinggear rotatably placed inside the chamber and having a plurality of gearteeth pressing and transferring the powder provided by the powder supplypart; and a transfer disk rotatably placed inside the chamber and havinga circular arc powder pressing groove receiving the compressed powdertransferred through the feeding gear.
 2. The apparatus of claim 1,wherein the driving part comprises a gear box comprising: a plurality ofgears receiving a rotational torque from outside and rotating at apredetermined speed ratio; and a plurality of rotation shafts fixed tothe gears and rotating about their axes by the rotation of the gears,and extending in a longitudinal direction.
 3. The apparatus of claim 2,wherein the powder supply part comprises: an upper plate fixed outsideof the gear box and through which one or more than one rotation shaftsof the plurality of rotation shafts passes; and a powder pushing unitequipped on the upper plate, rotating clockwise or counter clockwise incontact with the upper surface of the upper plate by the rotationshafts, and transferring the powder to the chamber.
 4. The apparatus ofclaim 2, wherein the chamber comprises a sub-supply block comprising: afirst space part with a predetermined diameter and depth opened towardthe powder supply part to receive the powder provided by the powdersupply part, and through which one of the rotation shafts of the gearbox passes upward and is disposed in the center thereof; and a secondspace part with a predetermined diameter and depth formed at the side ofthe first space part, opened to the first space part to receive thepowder from the first space part, and through which another rotationshaft of the gear box passes upward and is disposed in the centerthereof.
 5. The apparatus of claim 4, wherein: the at least one feedinggear of the compression part is placed inside the first space part andis rotated by the rotation shafts; the transfer disk is placed insidethe second space part and is rotated by the rotation shafts; and a covermain body partly covering the powder pressing groove and supporting thepowder to the powder pressing groove is placed on the transfer disk. 6.The apparatus of claim 5, wherein the quantitative supply part comprisesa blade having a leading end part entering into the powder pressinggroove, partly cutting the compressed powder in the powder pressinggroove during the rotation of the transfer disk, and discharging the cutpowder from the second space part.
 7. The apparatus of claim 5, furthercomprising; a crushing pin fixed in the cover main body, crushing thecompressed bulk of powder while the bridged powder is being transferredand compressed by the feeding gear, and transferring the crushed powderto the powder pressing groove.
 8. The apparatus of claim 5, wherein thetransfer disk comprises: an inner disk having a predetermined diameterand rotating by the rotation shaft; an outside ring having the same axisas the inner disk, and the inner circumference spaced apart from theexterior circumference of the inner disk forming the powder pressinggroove; and a packing member inserted into the lower part of the powderpressing groove and upwardly supporting the powder stored in the powderpressing groove.
 9. The apparatus of claim 8, wherein a projection isformed at the bottom part of the second space part to press the powderapproaching the blade to the cover main body by moving the packingmember of the transfer disk upward.
 10. The apparatus of claim 3,further comprising: a powder storing case attached to the upper part ofthe upper plate and storing powder to be provided from outside in whichthe upper part acts as a bottom surface, wherein the powder pushing unitcomprises; a fixing unit fixed to the rotation shaft and beingsymmetrical around the rotation shaft; a tip unit placed in both ends ofthe fixing unit and moving in a length direction of the fixing unit; anda spring disposed between the fixing unit and the tip unit andelastically supporting the tip from the fixing unit to externally,wherein two or more projections temporally compressing the tip unit ofthe pushing unit to the fixing unit during the rotation of the pushingunit are formed in the inner circumference of the powder storing case.11. The apparatus of claim 3, further comprising: a porous plate spacedparallel apart from the upper plate in the inner surface of the powderstoring case and having a plurality of through holes passing downwardthe powder provided from outside; and an auxiliary rotor placed on theupper surface of the porous plate, rotating by the rotation shaft, andinducing the powder to the through holes.
 12. A material supplyapparatus comprising: an upper duct passing an externally providedplastic raw material; a quantitative powder supply apparatus inaccordance with claim 1 supplying powder to be mixed with the plasticraw material into the upper duct; a rotation duct rotatably equipped atthe lower part of the upper duct and including a stirring unit mixingthe plastic raw material with the powder; a lower duct placed below thelower part of the rotation duct, rotatably supporting the rotation duct,and discharging a mixture of the plastic raw material and powderdownwardly that passes through the rotation duct to the outside;bearings disposed between the upper duct and the rotation duct andbetween the lower duct and the rotation duct, rotatably supporting therotation duct, and forming a seal between the rotation duct and theupper and lower ducts; and a driving unit axis-rotating the rotationduct and operating the stirring unit.
 13. The material supply apparatusof claim 12, wherein the stirring unit is at least one steel wire fixedin the inner circumference of the rotation duct.
 14. An apparatus forsupplying powder quantitatively to a place where required, the apparatuscomprising: a driving part generating a driving force using an externalpower; a powder supply part connected to the driving part, following theoperation of the driving part, and transferring the powder according toa predetermined path; a chamber placed on the sides of the powder supplypart and receiving the powder transferred by the powder supply part; acompression part compressing the transferred powder in the chamber; anda quantitative supply part separating a desired amount of powder fromthe compressed powder and discharging the separated powder from thechamber, wherein the chamber comprises a sub-supply block including: afirst space part with a predetermined diameter and depth opened towardthe powder supply part to receive the powder provided by the powdersupply part; and a second space part with a predetermined diameter anddepth formed at the side of the first space part, and opened to thefirst space part to receive the powder from the first space part. 15.The apparatus of claim 14, wherein the driving part comprises a gear boxincluding: a plurality of gears receiving a rotational torque fromoutside and rotating at a predetermined speed ratio; and a plurality ofrotation shafts fixed to the gears and rotating about their axes by therotation of the gears, and extending in a longitudinal direction, andwherein one of the rotation shafts of the gear box passes upward throughthe first space part of the chamber and is disposed in the center of thefirst space part, and another rotation shaft of the gear box passesupward through the second space part and is disposed in the center ofthe second space part.